Some of those eager to immerse themselves in Altair's portable crusade in Assassin's Creed: Bloodlines have allegedly been denied entry into the Animus. This has, in turn, led to animosity being expressed on Sony's message boards and our tips line. According to complaints, the downloadable version (the game is also available on UMD) freezes during its initial loading screen, regardless of PSP model.
Based on user comments, the hobbled file originated from the European PlayStation Store and has since been bumped off -- to be replaced with a working version soon, hopefully. We'll keep an eye on things (and your comments below) while we await a response from Ubisoft.
Update: Sony has replaced the faulty download and offered replacement codes to those affected.
Source -- Official PlayStation Forums
Source -- EU PlayStation Blog comments
Source -- Youtube video [Thanks, Gian]